It is known that the coordinates of vertex A and B of square ABCD are a (1,0), B (5,3) respectively, and point D is in the second quadrant

It is known that the coordinates of vertex A and B of square ABCD are a (1,0), B (5,3) respectively, and point D is in the second quadrant

D is in the second quadrant, so AB can only be one side of a square. Make a vertical line de from point D and a vertical line BF from point B perpendicular to the X axis, then the triangle ade and the triangle BAF are congruent, and you can directly calculate that the D coordinate is (- 2,4). Therefore, because AB and CD are parallel and equal, you can deduce that the C coordinate is (2,7)